Insulation-penetrating clip-type electrical connectors



e. 8, 1966 LOGAN 3,234,498

INSULATION-PENETRATING CLIP-TYPE ELECTRICAL CONNECTORS Filed June 4.,1965 2. Sheets-Sheet 1 INVENTOR. A. LOGAN ATTORNEY Feb. 8, 1966 A. LOGAN3,234,498

INSULATION-PENETRATING CLIP-TYPE ELECTRICAL CONNECTORS Filed June 4,1963 2 Sheets-Sheet 2 QK R\ hwy uL wwm m cm nw vkmL MLEYL United StatesPatent Ofiice Patented Feb. 8, 1966 3,234,498 INSULATTON-PENETRATINGCUP-TYPE ELECTRICAL C(BNNECTORS Alexander Logan, Stoneleigh, Mi,assignor to Western Electric Company, Incorporated, New York, N.Y., a

corporation of New York Filed June 4, 1963, Ser. No. 285,339 4 Claims.(Ci. 339-97) This invention relates to devices for mechanicallyretaining and electrically contacting conductors. More particularly,this invention relates to corrosion resistant cliptype electricalconnectors for penetrating the insulation of electrical conductors toconnect such conductors without first removing the insulation therefrom.

Clip-type electrical connectors of the prior art have been used tomechanically retain and electrically contact insulated conductorswithout first removing the insulation from the conductor. (See copendingapplication Serial No. 182,560 now Patent No. 3,112,147 filed on March26, 1962 by W. Pferd, K. H. Pohland and D. W. Tyler.) Such connectorsinclude a pair of elongated, contigous, contacting jaws formed from aresilient, electrically conductive material, such as Phosphor bronze orthe like. The insulated conductor to be joined to the connnector isforced between the contiguous jaws to space them apart a slightdistance. Due to the resiliency of the jaws, they tend to close orre-obtain their contiguous state, thereby penetrating or tearing apartthe insulation and tightly clamping the conductor. Thus, the connectormechanically retains and electrically contacts the conductor.

In using these connectors in moist or corrosive environments, thecontacting faces of the resilient jaws have developed nonconductingcoatings which interfere with both the electrical connection andmechanical retention of the conductor. However, if the contacting facesof the jaws could be plated with a corrosion resistant conductive metal,such as tin or the like, and if this plating would in no way interferewith the resiliency of the jaws of the connector, the connectors couldbe used in moist or corrosive environments. Moreover, such plating couldincrease the wear resistance of the jaws. Accordingly, it is necessaryto space apart the contiguous contacting jaws prior to the joining of aconductor thereto a sufficient distance to permit the plating of thefaces of such jaws and at the same time without sacrificing theresiliency of the contacting jaws. Moreover, the spacing of the jawsmust be equal to a distance of less than the diameter of the conductorto be joined to the connector to thereby enable the jaws to exert asufficient force on the conductor to securely hold it and provide a goodelectrical connection.

It is, therefore, an object of this invention to provide new andimproved devices for mechanically retaining and electrically contactingconductors.

Another object of this invention is the provision of clip-typeconnectors for interconnecting a plurality of electrical conductorswithout first removing the insulation therefrom.

A further object of this invention is the provision of a clip-typeelectrical terminal block having a plurality of pairs of wear andcorrosion resistant resilient jaws, which are spaced apart apredetermined distance, for penetrating the insulation of an electricalconductor and tightly elements, holds the free ends thereof apart adistance equal to less than the diameter of the conductor.

Other objects and advantages of the invention may be more clearlyunderstood by reference to the following description in the accompanyingdrawings, wherein:

FIG. 1 is an enlarged, fragmentary, front-elevational view of anelectrical connector, clearly showing the spaced relationship of thejaws of the connector and the deformation of the inner edges of suchjaws for maintaining this spaced relationship;

FIG. 2 is a perspective view of a terminal block incorporating a vastnumber of the connectors of FIG. 1 and illustrates the manner in which aplurality of insulated conductors are either joined to, or temporarilyheld by, the connectors;

FIG. 3 is an enlarged, fragmentary perspective view, showing how aninsulated conductor is securely joined to the jaws of the connector andhow the terminal block for supporting the connector prevents theconductor from sliding downwardly beyond a predetermined portion of thejaws into an aperture formed between such jaws;

FIG. 4 is a schematic, front-elevational view of an apparatus for makingthe electrical connectors in accordance with the present invention; and

FIG. 5 is a plan view of a strip of electrically conductive resilientmaterial from which the connectors are formed.

Referring now to the drawings, and more particularly to FIG. 1, there isshown a device or a clip-type connector 11 for mechanically retainingand electrically contacting an insulated conductor 12, FIGS. 2 and 3.The connector 11 is formed from a sheet of resilient, electricallyconductive material such as Phosphor bronze or the like.

The connector 11 includes first and second elongated elements or jaws 13and 14 joined at one end by a base portion 16 and free at the other end.The free end of the first jaw 13 has a rounded portion 17 while the freeend of the second jaw 14 has a sidewise rounded protruding portion orhook 18 extending partially over the rounded portion 17. The roundedportion 17 coacts with the hook 18 to form a V-shapedconductor-receiving passageway 19 in which an insulated electricalconductor 12 may be conveniently placed and held, as shown in FIG. 2,before such conductor 12 is forced down between the jaws 13 and 14, asshown in FIG. 3. Moreover, the roundness of the portion 17 and hook 18prevents the jaws 13 and 14 from piercing, tearing or injuring in anyway the insulation of the conductor 12 as it is being positioned in, oras it is being temporarily held by, the passageway 19. In addition, thehook 18 of the jaw 14, which is longer than the jaw 13, in conjunctionwith the V- shaped conductor-receiving passageway 19, greatlyfacilitates the positioning of the conductor 12 within such passageway19. Also, the V-shaped passageway 19 provides an inclined plane againstthe conductor 12 as it is forced downwardly between the jaws 13 and 14to slowly open such jaws 13 and 14 and slideably receive the conductor12.

Formed between the jaws 13 and 14 is a slot 21, the dimensions of whichdetermine the forces exerted by these jaws 13 and 14 against theconductor 12 when it is forced therebetween, as shown in FIG. 3, and asdis closed in the aforementioned application Serial No. 182,- 560 filedMarch 26, 1962. Moreover, an aperture 22 located above the slot 21 isformed between the jaws 13 and 14. The aperture 2.2, in cooperation withthe slot 21, defines the length of portions or protuberances 23 producedby plastically deforming the inner edges of the jaws 13 and 14. Thefunction of the deformed portions 23 is to resiliently hold apart thejaws 13 and 14 to establish a space 24 between such jaws 13 and 14. The

lateral dimension of this space 24 is critical. Such dimension must beless than the diameter of the conductive part of the insulated conductor12, but must be sufficiently large to permit plating of the inner edgesof the inner edges of the jaws 13 and 14 which contact the conductor 12.For a 24 gauge insulated conductor, this lateral dimensions is equal to0.005 inch.

, As shown in FIG. 2, a plurality of the connectors 11 are joined'together by the base portions 16 thereof, and a group of such joinedconnectors 11, are mounted in a terminal block 26 to form a unit.Securely holding the connectors 11 Within the block 26 is a base 27secured to. the block 26 by threaded members 23. As is apparent. fromFIG. 3, the terminal block 26, in addition to holding a group of joinedconnectors 11, prevents the conductor 12 from sliding too far down thejaws 13 and 14 and into the apertures 22 of the connectors 11.

Also, as is illustrated in FIG. 2, a plurality of electrical conductors12 may be temporarily held by the V- shaped pasageways 19 of theconnectors 11.

On the other hand, with the aid of the inclined edges of the passageway19, one of the conductors 12 may be slideably forced down beyond suchpassageway 19, between thejaws 13 and 14, and into the space 24. As theconductor 12 is forced into the space 24, the jaws 13 and 14 areresiliently opened by the conductor 12. Since the jaws 13 and 14 areresiliently biased toward each other, the inner edges of such jaws 13and 14 pierce or tear apart the insulation of the conductor 12 and biteinto the conductor 12 to mechanically retain such conductor 12 withgreat force and make a good electrical connection between the conductor12 and connector 11.

Shown in- FIG. 4 is a schematic of an apparatus for making the clip-typeelectrical connectors 11 joined together by base portions 16 inaccordance with the present invention. In making such connectors 11, astrip of electrically conductive resilient material 31, such as Phosphorbronze or the like, is advanced from a supply reel 32 to a take-up reel33. The take-up reel 33 is driven by a conventional indexing motor 34through a standard V belt drive 36.

The material 31 is initially advanced to a punching station 37;whereupon the material 31 is stopped by the indexing motor 34. Then, amotor 39 rotates a shaft 41 to rotate a cam 42. Rotation of the cam 42pushes a punch 43 through the material 31 into a die 44 to form aplurality of aligned apertures 46, perpendicular to the longitudinaledges ofthe'material 31, as shown in FIG. 5. I

After the apertures 46 are formed in the material 31, the indexing motor34 advances the material 31 to move the apertures 46 to aposition justin front of a second punching station 47. Next, the motor 34 stops thematerial 31. Then, the motor 39 rotates the shaft 41 to rotate a cam 48.The rotation of the cam 48 then pushes a punch 49 through the material31 into a die 50 to produce a plurality of slots 51 (FIG. in front ofeach aperture .46. At the same time that the slots 51 are formed in thematerial 31, a second series of apertures 46 are also produced at thefirst punching station 37.

Upon the formation of the slots 51 in the material 31, the indexingmotor 34 advances the material 31 to a third punching station 52 where aplurality of openings 53 are formed in the material 31 in the samemanner that the slots 51 are formed in the material 31. The openings 53are clearly shown in FIG. 5.

Again, the indexing motor 34 advances the material 31, but this time toa shearing station 54 where a first portion of the material 31 issheared, as shown at 55 in FIG. 5, by a movable shear 56 which coactswith a stationary shear 57. This shearing of the material 31 joins theslots 51 with the apertures 46 and, further, defines the second jaw 14,asillustrated in FIG. 5. Such shearingaction is controlled by the motor39, in the same manner that the punching action at stations 37' and 38is controlled by the motor 39.

Next, the material 31 is advanced by the indexing motor 34 to anothershearing station 58; whereupon, the material 31 is again sheared, asclearly shown at 59 (FIG. 5), to form the first jaw 13. This shearing isaccomplished in the same way that the shearing at the station 54 isaccomplished.

The material 31 is then advanced to a deforming station 61 where theinner edges of the jaws 13 and 14 are stamped, coined or plasticallydeformed by a movable stamping die 62 which coacts with a stationaryplaten 63 to form the portions 23 to thereby space such jaws 13 and 14.This stamping operation is controlled by the motor 39 in the same mannerthat such motor controls the punching and shearing operations at theother stations 37, 47, 52, 54 and 58.

After the stamping operation, the indexing motor 34 advances thematerial 31 to a blanking station 64. At this station 64, the jaws 13and 14 are blanked from the strip 31 in such a manner that such jaws 13and 14 are joined together by the base portion 16 to form the connector11, and a group of such connectors 11 are also joined together by agroup of such base portions 16. The blanking dies, which are of theconventional type, are controlled by the motor 39 in the same mannerthat the punching and shearing operations are controlled by such motor39 at the other stations 37, 4'7, 52, 54, 53 and 61. After theconnectors 11 are blanked from the strip 31, they fall into and arecollected by abin 66.

Next, the connector-s 11 are plated with a wear and corrosion resistant,electrically conductive material which does not interfere with theresiliency of the jaws 13 and 14. Since the jaws 13 and 14 are spaced bythe deformedportions 23, such plating may be efI'ectuated at the inneredges of the jaws 13 and 14, which bite into the conductor 12 when it isforced into the space 24 between such jaws 13 and 14.

As to the thickness of the plated material, it must be sutficiently thinso as not to interfere with or block up the space 24 between the jaws 13and 14.

An example of a satisfactory plating material is tin Which may be veryeasily electroplated in accordance with conventional techniques andtypically is plated to a thickness of about 0.0001 inch.

Inasmuch as the connectors 11, which may be more efiicaciously utilizedby being positioned within the terminal block 26, are plated with acorrosion resistant material, they may be utilized in a moist, corrosiveenvironment and such connectors 11 would not develop nonconductingcoatings on the inner faces of the jaws 13 and 14 which would interferewith the electrical connection and the mechanical retention of theelectrical conductors 12'.

Since the connector 11 is formed first by shearing the jaws 13 and 14from the material 31 with no space 2 4 between such jaws 13 and 14', andthen the jaws 13 and 14 are subsequently plastically deformed to producethe portions 23 to space apart such jaws 13 and 14 to establish thespace 24 therebetween, the force tending to close the space 24 betweenthe jaws 13 and 14 is the same as if the connector 11 were formed withno space 24. Thus,

the jaws 13 and 14 of'the connector 11 have the same ability topenetrate and tear apart the insulation to tightly clamp and bite intothe conductive part of the insulated conductor 12 as the jaws 1-3 and 14would have if there were no space 24 between them. In other words, theprovision of the space 24 between the jaws 13 and 14 does not sacrificethe resiliency of the jaws 13 and 14 nor the force which the jaws 13 and14 exert on an insulated conductor forced between such jaws 13- and 14and into the space 24. Moreover, with the space 24 between the jaws 13and 14, such jaws 13 and 14 may be easily plated, as mentioned above,with a wear and corrosion resistant material such as tin or the like andthe connector 11 may be readily utilized in an unfavorable environment.

It is to be understood that the above-described product forms y oneembodiment of the present invention, and

numerous products may be derived from the abovedescribed embodimentwithout departing from the spirit and scope of the invention.

What is claimed is:

1. An insulation-penetrating terminal connector for an 5 insulatedelectrical conductor, comprising:

a pair of electrically conductive elongated elements having opposingfree ends and an integral base section for supporting said free ends,

said base section biasing said free ends toward one another,

a pair of mutually opposed edges on the elements for shearing insulationfrom a conductor inserted therebetween, and

a least one protuberance projecting from one of said edges into anabutting relationship with a mutually opposed edge for forcing saidelements apart against 3. An insulation-penetrating terminal connectorfor an insulated electrical conductor, comprising:

bifurcated electrically conductive elongated elements having free endsand an integral base section for supporting said free ends,

said base section biasing said free ends toward contact with oneanother,

a pair of mutually opposed edges on the bifurcated elements for shearinginsulation from a conductor inserted therebetween, and

a protuberance formed on at least one of the opposed edges and locatedbetween the extremities of said free ends and said base section forforcing said elements apart a distance less than the diameter of theconductor against the bias applied by said base section, so that saidelements are in a prestressed insulationshearing state prior toreceiving the conductor.

the bias applied by said base section so that said elements are in aprestressed insulation-shearing state 4. The connector as claimed inclaim 3, wherein at least said mutually opposed edges of said connectorare prior to receiving the conductor. 2. An insulation-penetratingterminal connector for an insulated electrical conductor, comprising:

a pair of electrically conductive elongated elements having bifurcatedfree ends and an integral base section for supporting said free ends,

said base section biasing said free ends toward contact with oneanother, pair of mutually opposed edges on the bifurcated elements forshearing insulation from a conductor inserted therebetween, and

a pair of mutually abutting protuberances formed integral with saidedges for forcing said elements apart a distance less than the diameterof the conductor against the bias applied by said base section, so that3 said elements are in a prestressed insulation-shearing state prior toreceiving the conductor.

plated with an electrically conductive, corrosion resisting material.

References Cited by the Examiner UNITED STATES PATENTS 2,539,230 1/1951Craig 339-278 X 2,545,352 3/1951 Gibbs 29155.55 2,610,390 9/1952 Locke29155.55 2,762,030 9/ 1956 Scoville 339277 2,828,474 3/1958 Fox 33947 X2,851,670 9/1958 Senior 339 2,933,007 4/1960 Healy 339220 X 2,962,69211/ 1960 White 339-220 3,027,536 3/1962 Pasternak 339-97 3,112,14711/1962 Pferd et a1. 33997 JOSEPH D. SEERS, Primary Examiner.

W. DONALD MILLER, Examiner.

1. AN INSULATION-PENETRATING TERMINAL CONNECTOR FOR AN INSULATED ELECTRICAL CONDUCTOR, COMPRISING: A PAIR OF ELECTRICALLY CONDUCTIVE ELONGATED ELEMENTS HAVING OPPOSING FREE ENDS AND AN INTEGRAL BASE SECTION FOR SUPPORTING SAID FREE ENDS, SAID BASE SECTION BIASING SAID FREE ENDS TOWARD ONE ANOTHER, A PAIR OF MUTUALLY OPPOSED EDGES ON THE ELEMENTS FOR SHEARING INSULATION FROM A CONDUCTOR INSERTED THEREBETWEEN, AND A LEAST ONE PROTUBERANCE PROJECTING FROM ONE OF SAID 